If you are convinced your dog is a genius, you may be disappointed in the conclusions of a study just published in the journal Learning and Behavior.The study finds that dogs are cognitively quite ordinary when compared to other carnivores, domestic animals, and social hunters. “There is no current case for canine exceptionalism,” the authors conclude.

That we think otherwise is not surprising. Claims of canine exceptionalism abound, from people’s anecdotes about their dogs’ ability to read their minds (“Sparky looked into my eyes and then at the refrigerator—he knew I wanted a beer!”), to books with titles such as My Dog is a Genius: How to Improve your Dog’s Intelligence, to a canine intelligence test that will let you “find the genius in your dog.”

Case studies add to the perception that dogs possess uncanny intelligence. A striking example is a Border collie named Chaser. Trained from puppyhood by her owner, the late Wofford College psychologist John Pilley, Chaser has learned the names of more than a thousand toys. She even seems able to reason, as she demonstrated for the astrophysicist Neil deGrasse Tyson on the television program NOVA. Tyson begins by placing a random selection of Chaser’s toys behind a couch and asking her to retrieve several of them, which she does with dispatch. He then adds to the array a toy she has never seen—a Charles Darwin doll. Finally, he asks Chaser to “find Darwin!” Chaser walks behind the couch, and after a few seconds of hesitation, brings the doll to an astonished Tyson.

Another reason we may think our dogs are gifted stems from the way we view ourselves. When people are asked to rate themselves on traits such as intelligence, they tend to give above-average ratings. This Lake Wobegon effect—named after the fictional town created by Garrison Keillor where “all the children are above average”—extends to pets. In a study published in Basic and Applied Social Psychology, researchers had 137 pet owners rate both their own pet and the average pet on a range of traits, including intelligence. The results revealed that the people rated their pets as above average on desirable traits and below average on undesirable traits.

Nevertheless, systematically reviewing the animal cognition literature, British psychologists Stephen Lea and Britta Osthaus found dogs to be unremarkable in their cognitive capabilities compared to wolves, cats, dolphins, chimpanzees, pigeons, and several other species. For example, dogs seem no better at learning associations—such as between a behavior and a reward—than other species. Similarly, dogs can spatially navigate within small spaces, but other species can, too. And while dogs have an excellent sense of smell, the “pig’s olfactory abilities are outstanding and might even be better than the dog’s.”

Even more surprising, dogs do not appear to be exceptional in their ability to perceive and use communicative signals from humans. According to the domestication hypothesis, dogs have been bred to be especially sensitive to human cues such as hand signals. As Lea and Osthaus note, dogs can indeed use human cues. However, contrary to the domestication hypothesis, they are far from unique in this ability. For example, the reigning champions of the ability to follow human hand signals are the bottlenose dolphin and the grey seal.

None of this is to diminish the benefits of dog ownership. They keep us company and may even improve our physical health. In a study published last year in NatureScientific Reports, Swedish researchers examined the relationship between dog ownership and cardiovascular health in a sample of nearly 3.5 million Swedish adults. As part of the public healthcare system, the Swedish government maintains registers of hospital visits and cause of death for all Swedish citizens and residents. Also, all dogs in Sweden must be registered with the government. The researchers were thus able to link health and dog ownership data.

Even after the researchers statistically controlled for age, education, and socioeconomic status, dog owners were significantly less likely to have had a heart attack and significantly less likely to have died from cardiovascular disease than non-dog owners were. What’s more, these benefits of dog ownership were largest for single people. While stressing that the results must be interpreted cautiously because they are correlational, the researchers suggest two possible explanations for the findings. The first is that owning a dog alleviates psychosocial stress caused by isolation and depression, which has been linked to cardiovascular disease. The second explanation is that dog owners, in taking their canine companions on walks, are more physically active.

So even if dogs can’t follow hand signals as well as a bottlenose dolphin and their sense of smell is no better than a pig’s, their effects on our lives may be remarkable all the same.

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